Greek-derived nouns ending in -on change to -a in the plural form.
Siphon is regular. It follows the Greek -a rule.
Use plural verbs: "The sipha are ready" (not "is ready").
Yes. The plural sipha is standard across all English variants.
The word siphon follows the standard English pluralization rule. When forming the plural, siphon becomes sipha. This follows the Greek -a pattern, which is one of the most common plural rules in English.
Understanding why siphon becomes sipha helps with spelling and pronunciation. Greek-derived nouns ending in -on change to -a in the plural form.
When using sipha in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The sipha are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.